1. Field of the Invention
This invention relates to adhesive compositions useful for restoration, including their use as light-curable dental cements, which possess improved bonding strength and curing property.
2. Description of the Prior Art
Glass ionomer dental cements are a new class of restorative material for use in dentistry. Compositions such as these have been in clinical use since 1975 in Europe and were introduced in the United States in 1977. Glass ionomer cements are composed of silica cement and polyacrylic acid, and have characteristics pertaining to both constituents.
Although glass ionomer cements have been accepted by dental practitioners, because they are tooth colored, bond to dentin and enamel, and contain fluoride ions, these cements have significant drawbacks. For example, glass ionomers are aesthetically inferior to dental composite resins, susceptible to water contamination, and relatively slow to cure. However, progress has been made in developing improved glass ionomer cements, as is illustrated in U.S. Pat. No. 4,738,722 to Ibsen, et al. The Ibsen patent describes a buffered glass ionomer dental cement which minimizes pulpal irritation upon application and expedites curing time.
This invention provides advances in the area of dentistry by offering unique adhesive restorations which release fluoride, and dual cured, can be radiopaque yet can be visually translucent, and bond to all dental substrates with minimum substrate preparation. Since the dental cement of this invention is non-aqueous, it has the additional property of increased resistance to dissolution.
Some of the above-noted properties of the dental adhesive are appreciated not only in dental uses, but for repairing or bonding a variety of materials. Thus, this invention also provides for restorative adhesives adapted for use in non-dental fields, such as repair glue or bone cement.